This invention concerns improvements in and relating to the consideration of evidence, particularly, but not exclusively the consideration of DNA evidence.
In many situations, particularly in forensic science, there is a need to consider one piece of evidence against one or more other pieces of evidence.
For instance, it may be desirable to compare a sample collected from a crime scene with a sample collected from a person, with a view to linking the two by comparing the characteristics of their DNA. This is an evidential consideration. The result may be used directly in criminal or civil legal proceedings. Such situations include instances where the sample from the crime scene is contributed to by more than one person.
In other instances, it may be desirable to establish the most likely matches between examples of characteristics of DNA samples stored on a database with a further sample. The most likely matches or links suggested may guide further investigations. This is an intelligence consideration.
In both of these instances, it is desirable to be able to express the strength or likelihood of the comparison made, a so called likelihood ratio.